Linux is not Unix, but it is a Unix-like operating system. Linux system is derived from Unix and it is a continuation of the basis of Unix design. Linux distributions are the most famous and healthiest example of the direct Unix derivatives. BSD (Berkley Software Distribution) is also an example of a Unix derivative.

Is Linux different from Unix?

Linux is a Unix clone,behaves like Unix but doesn’t contain its code. Unix contain a completely different coding developed by AT&T Labs. Linux is just the kernel. Unix is a complete package of Operating system.

Does Unix still exist?

So nowadays Unix is dead, except for some specific industries using POWER or HP-UX. There are a lot of Solaris fan-boys still out there, but they are dwindling. BSD folks is probably most useful ‘real’ Unix if you are interested in OSS stuff.